% Copyright 2020 Makani Technologies LLC
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% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
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%      http://www.apache.org/licenses/LICENSE-2.0
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function [dcm] = mrp_to_dcm(p)
d = (1 + p'*p)^2;
dcm = eye(3) - 4*(1 - p'*p)*vcross(p)/d + 8*vcross(p)*vcross(p)/d;